Method of making plaster board



Sept. 21 1926.

J. F. MAKOWSKI METHOD OF MAKING PLASTER BOARD Filed March 4, 1924 5Sheets-Sheet 1 Sept. 21 1926.

J. F. MAKOWSKI METHOD OF MAKING PLASTER BOARD 1924 3 Sheets-Sheet 2Fig.2

Filed March 4,,

I N VEN TOR. cf. Ffmowski (3% .&A .&,SL

ATTORNEY Sept. 21 1926.

3 Sheets-Sheet 5 INVENTOR cf. FMaKoLI/KSR i Q 1mm ATTORNEY PatentedSept. 21,1926. i 1,000,550

UNITED STATES PATENT OFFICE.

JOHN F. KAKOWSKI, OI STOCKTON, CALIFORNIA, ASSIGNOB TO CALIFORNIA CEDAR'PRODUCTS COMPANY, OF STOCKTON, CALIFORNIA j un'rnon or MAKING ILASTER130m.

Application filed 1mm 4, 1924. Serial No. 696,769.

This invention relatesto the plaster board machine is shown anddescribed in my comaking art, the object of the mvention bependingapplication for patent, Serial No. ing to evolve a method wherebyplaster 682,484 filed December 24th, 1923. board may be successfullymade with the use The methodcan probably however be car- 6 of paperwhich is not treated to retard the ried out with other machines so I donot wish permeation of moisture. Due to the fact to be understood aslimiting myself in that that it has heretofore been found somewhat reard.

difficult to make plaster board from unreor a clear understanding of themethod tarded paper a number of manufacturers I am showing in thisapplication a brief out- 10 have adhered to the use of the treated paperline of the machine used at present to illusalthough there are numerousobjectlonable trate how the several steps of the method features whichdevelop in wall board made may be carried out.-

therefrom. Plaster board made from the A further object of the inventionis to unretardedpaper however is free from these produce a simple andinexpensive device and objectionable features and also the use thereyetone which will be exceedin 1y effective 66 of reduces the cost ofmanufacture and I for the purposes for which it is esigned.

have therefore, after considerable experi- These objects I accomplish bymeans of ment, overcome the difficulties heretofore exsuch structure andrelative arrangement ofperienced in the attempts to use the unreparts aswill fully appear by a perusal of- 20 tarded paper and have evolved amethod the following specification and claims. 70 whereby the same canbe successively used in In the drawings similar characters of refthemanufacture of plaster board. erence indicate corresponding parts in theIn order that my invention may be the several views:- more readilyunderstood I Wlll first point Fig. 1 is a side. elevation, foreshortenedout the reasons why it'is difficult to handle in places, of thecomplete'machine, showing the unretarded paper. The paper usually aboard as being drawn over and onto a stack used is commonly known aschip board and of the same. it absorbs moisture very rapldly when notFig. 2 is an enlarged vertical section of treated to retard suchabsorption. The plasthe vertically movable apron and cutting ter boardis made of considerable initial. lem nts, and the tru k carrying thvertilength and width so that as the moist uncally movable jaw orgripping means, showstable plaster is introduced between the paper ingthe latter in position to engage the adthe weight is of considerablemoment. jaeent end of th board,

The plaster board in its most unstable Fig. 3 is a fragmentary side viewof the condition must be pulled out as It is formed, apron structure,showing the movable (gutter to be laid fiat so as to allow the plastert0 and the movable board-supporting surface h d d et. It. is thispulling operain position to co-act with said movable tion, when takenwith the weight involved, tt r,

a which has been hard to accomplish With the Fig, 4 is a similar iewhowing the, jaw

4 unretarded paper as the same becomes 1nraising operating mechanism,mounted on stantly moist and tender .from the moisture th t k, in theplastic mass and thus is easily torn, Fi 5 i f o t vi f th ro andbuckled or scuffed. which renders the board tti t u tur s, 1non-commercial. My method therefore 18 Fig. 6 is a similar view of thejaw strucdesigned to allow the board, as-formed f ture, the truck fromwhich said structure deunretarded paper, to be pulled out and laid pendsbeing omitted.

. flat for hardening and setting without any Referring now moreparticularly to the -of these deleterious efiects. characters ofreference on the drawings the I have devised one eflicient machine fornumerals 1 and 2 designate the board form- 50 carrying out my improvedmethod, which ing rollers which are positively driven in any suitablemanner (not shown) and which are spaced apart the desired distance tomake the board of uniform thickness.

The numeral 3 designates one roll of paper positioned at a point belowthe rollers 1 and 2, and 4 designates the other roll of paper located ata point above the rollers l and 2.

In the manufacture of the plaster board the paper from the roll 3 isfirst advanced over a flat platform 5 at which point the moist unstablemass of plaster 6 is fed'thereon from the hopper 7.

The paper 3 with the plastic mass thereon then advances between therollers l and 2,

and the paper from the roll 4 comes around the roller 2 and between therollersl and 2. Thus the two sheets of paper are adhered by the rollers1 and 2 to the plastic mass 6 at a uniform thickness, thus forming theplaster board 8 which will hereinafter, for the sake of brevity, bereferred to as the board.

Positioned after the rollers 1 and 2 is a drag draper belt 9 driven bypositively driven rollers 10 and 11.. This draper is slightly wider thanthe board 8 and of desired length to properly carry out its function inperforming one step in my .new method. The rollers 10 and-11 are smallerthan the rollers 1 and 2 but travel at the same R. P. M. for apurposeas. will presently appear.

The board 8 passing from between the rollers 1 and 2 is laid flat on thedraper 9. The surface papers of the board being readily permeable bymoisture, a portion of the moisture in the plastic mass between thesheets permeates to the outside of the sheets. Thus the moistened paperplus the weight of the board causes the board to have strong frictionalsurface contact with the drag draper 9, to pull the same through therollers land 2.

The roller 4 is weighted by a strap 12 and weight 13 so as to have itsmovement retarded. The roller 2 is provided with a highly polishedsurface. Thus, unless the drag of the draper is on the board the roller2 will slip within the paper similar to a. warping. drum and will notfunction to press the plastic mass between the papers except when thefrictional drag of the draper is had thereagainst. This action preventsthe pressure of the rollers 1 and 2 from tending to buckle the board inthe area between the rollers and the drag draper as will be obvious.

The roller 2 is slightly larger in diameter than the rollers 10 and 11but is drivenat the same R. P. M. Thus the tensile stretch or pull onthe paper as it leaves the rollers 1 and 2 is eased sufiiciently toprevent tearing, while atthe same time bucklingis prevented by thewarping action described above.

. From the foregoing description it will be obvious that the only dragimparted to the board during its formation Wlll be that of the draper 9,while the pushing action of the roller 2 is such as to ease this drag tothe proper degree to revent tearing. The pull on the papers 0 the boardwill therefore be uniform over the entire surface area of the board sothat no one oint will be subjected to greater tearing, uckling orbreaking strain than any other. Qonsequentl no tearing, breaking, buck-1mg or scu ng will occur in the formation of the board. Therefore thetender, unre tarded and readily moistened paper can be handled with thegreatest ease.

The board having thus been formed without any disastrous effects, thenext problem I is to be able to stack it for hardening and setting,prior to drying same, which operation must of course be alsoaccomplished. I

without tearing, board.

The real drag on the board is incurred in the initial formation thereofas already, described. To stack requires only that its own weight mustbe sustained and carried along over the stack. This however isconsiderable and the same cannot be successively carried out by hand,since the sheet of board to be stacked is still limber and scuffing orbuckling the under the hand method of stacking will sagdown and drag onthe top of the top sheet of the stack and get torn and scuffed by suchdragging contact. a

It becomes necessary therefore .to carry the sheet of board over thestack in a constantly suspended position with the contact between thesheet to be piled and the top sheet of the pile as light as possible toprevent scufling, and yet just enough to prevent the board from saggingto the breaking point. This I accomplish inthe following manner:

As the board 8 leaves the draper 9 it is passed over an apron 14 whichapron is mounted for rocking and sliding action on an upstanding support15 adjacent. the

The weight of the apron, sleeves, and

other parts connected thereto, is counterbalanced by means of weights 20to which are connected cables 21 passing over pulleys 22 mounted on theadjacent beams 19 and then extending down to connections with thecorresponding sleeves 17.

Vertical movement is imparted ,to the sleeves, and consequently to themembers attached thereto, by means of vertical rackbars 23 secured tothe platform 16 and engaged by pinions 24 mounted on a shaft 25journaled in bearing members 26 fixed on the posts 18.

' A handwheel 27 is jointed on the shaft at one end to enable said shaftto be easily turned.

Hinged or pivoted along the transverse edge of the platform 16 oppositeto the apron 14 is a short apron or board supporting surface 28, theupper faces of the apron 14, platform 16 and member 28 being arranged toform a continuous supporting surface without steps or offsets.

The member 28 is normally held in a substantially horizontal position bymeans of a handle 29 rigidly attached thereto, and which normallyextends horizontally beyond the hinged edge of the member 28, therebyacting as a counterweight and holding the said member up so that itsedge abuts against the adjacent edge of the platform 16, preventingfurther upward movement ofthe former.

A movable cutting member is provided to co-act with the free or outeredge of the member 28 when the latter is in its uppermost position,which comprises avertical cutting disc 30, whose lower edge is below theplane of said outer edge of the member 28 when the latter is in theabove named position.

The cutter 30 is turnably mounted on a frame structure 31 which isslidably mounted on a guide-bar 32 extending transversely of the racks23 and secured thereto by means of brackets 33.

A transversely disposed and horizontal pull-rod 34 is attached to theframe 31, and is of such a length that it may be easily reached by anoperator on one side of the machine when the cutter is on the otherside. The guide bar 32 is preferably of such a length that the cuttermay be moved clear of the member 28 at both ends thereof.

The beams 19 extend for a considerable distance beyond the apronstructure, and

' parallel to the ground, and have rails 35 mounted thereon on whichride the wheels of a carriage or truck 36. from whiclrdepends inside orbetween the beams, a rigid frame structure 37 of suitable design,forming a guide for transversely spaced rack bars 38, to the lower endsof which, and extending therebetween, is secured a transverse andhorizontal jaw member 39.

slidably mounted on the racks above said lower jaw member is acooperating and relatively movable jaw member 40 which is raised andlowered at will by means of pinions 41 meshing with certain teeth 42 ofj the racks.

The pinions are fixed on a shaft 43 j0ur-' naled in boxes 44 mounted onthe jaw 40, said shaft having on one end a handle 45 whereby the shaftmay be rotated, thus causing the jaw 40 to move toward or away from, thejaw .39.

The racks 38 are also engaged with pin ions 46 mounted on a transverseshaft 47, journaled in brackets 48 or the like fixed on the framestructure 37.

Also mounted on said shaft are ratchet wheels 49 engaged by pawls 50,these parts being arranged to prevent rotation of the shaft in a mannerwhich would permit lowering of the racks.

The pawls however are mounted on a. shaft 51 turnable at will by meansof a handle 52, so that said pawls, by turning the shaft, may be movedclear of the ratchet wheels at will. The handle 52 is arranged tonormally act as a gravity of weight means for holding the pawls engaged,obviating the use of SPIIIIgS.

Likewise mounted on the shaft 47 is an additional ratchet wheel 53engaged by apawl 54 mounted on a lever 55 which is turnable on the shaft47, said lever being adapted to be engaged and moved about the shaftwhen the jaws approach the member 28 by a rigid arm 56 projecting fromone of the posts 18, or from one of the bearing members 26.

The truck is limited in its movement toward the apron and cutterstructure by any suitable means, such as a stop 57 on the track 35, thejaws then projecting beyond the cutter a distance sufficientto causethem to receive the cut end of the board 8 therebetween, as shown inFig. 2. At the same time, the lever 55 will have been rotated by contactwith the arm 56 a distance sufficient to cause the racks 38, andconsequently the jaws, to be raised a distance equal to the thickness ofa sheet of the boar-d. \Vhen the lever disengages from the arm 56, theformer is returned to its normal position by a spring 58 or othersuitable means, the racks 38 being held from downward movement by reasonof the pawls 5O whibh engage the ratchet wheels 49.

The arm 56 and lever 55 may however be omitted if desired, and the shaft47 turned directly by hand.

When the truck 36 approaches its limit of desired movement away from theapron structure, it engages and throws an arm 59 connected to the clutch63 by suitable connecting means indicated diagrammatically at 60,whereby the clutch is automatically disengaged by the truck as thelatter reaches its limit of movement away from the apron.

This automatic clutch-throw device however forms no part of thepresentinventlon, since it is fully set forth and claimed in my aforementioned'copending application.

Also, any suitable means may be employed to move the truck 36 back andforth. Such features however also form no part of the present invention,and the truck may be considered to be moved by handa method of Imanipulation which has been successfully apron 14. by

used with the present apparatus, on account of the improved features ofconstruction, whereas it could not be so employed with the previousmachine.

On the floor under the tracks and in parallel alinement therewith aretracks 61 to form supports for a wheeled truck 62 of sufiicient size tosupport a stack of the board 9, as shown in Fig. 1.

This truck is positioned so that one end extends beyond and under the aron 28 and the other end is beyond the 'mit of travel of the truck 36away from said apron. v

The operation of the apparatusis as a1 lows: i

The board, formed at the time it asses between the rolls 1 and 2 asprevious y descrlbed, and then in a very wet and green condition, ismoved toward and onto the the constantly moving belt 10 on which theboard rests.'-

As soon as the end of the board reaches the plane of the cutter 30(assuming that this is the first board made from a fresh supply ofstock), the belt is halted, the

I apron 28 is depressed by raising up on the handle 29, and the truck 36is then moved toward said apron so that the jaws carried thereby may beengaged with the end of the I board which then projects clear of thedepressed apron. The latter is preferably not owered until'the jaws aread acent thereto, in order to avoid a saging down of the wet board,which might happen even though only a very short length of the same isunsupported. The upper jaw is then clamped onto the lower jaw by theraising of the handle 4:5 by an operator.

Previous to this, assuming the truck 62 to be empty, the platform 16 hasbeen lowered, by manipulation of the hand wheel 27, until the apron 28is within a few inches from the floor of the truck. The jaws 39 and 40have also been lowered to substantially the same and resting on thefixed support 15 at the other end always provides a continuoussupporting surface for the board from the belt 9 to the platform 16.

The jaws beingengaged with the board as above stated, the power isagainapplied to the belt 9, and the truck 36 is then moved along and awayfrom the belt by hand or otherwise, an operator holding the handle 45 soas to maintain the grip of the jaws on the board.

Due to the fact that a considerable len th of the board is resting onthe belt 9 an is belng constantly moved forward at an even rate thereby,only sufficient driving pressure is applied to the truck 36 to keep itmovmg at the same rate as the belt and so that it rests very lightly onthe truck 62. In other words, this movement is not fast enough to exertundue tensile strain on the board beyond the belt, nor yet so slow thatthe positively driven portion of the board has a tendency to fold overonto itself as the outer and slack portion comes to rest on the truck62. The latter provides a supportm surface for the slack portion of theoard et-ween its raised and definitely supported ends as it is beingdrawn along by the truck, and as such ends are held but a few inchesabove the truck surface, there is but little sag or drop of the boardbetween its ends, and hence no tendency for the board to pull apart andbreak of its own weight. As the truck 36 is moved along, the apron 28may be left. in its uppermost position, or may be lowered somewhat. Alsothe apron unit as a whole may be vertically adjusted the operator duringthis period if des1red, any such movement being left to the judgment ofthe operator and depending on the distance it may be desired to have theboard unsupported between the apron 28 and the truck 62.

When the truck 36 has advanced until the clutch-throw arm 59 is engagedthereby, the travel of the belt 9 and board 8 thereon is discontinued.The truck operator will at the same time release the handle 45, allowingthe jaws to open and the adjacent end of the board to drop fromtherebetween onto the truck 62. No difiiculty is experienced in timingthe handle-releasing movement of the operator with the throwing of theclutch 13, since when said truck strikes the throw arm 39 a resistanceto the continued movement of the truck is at once had, which is felt bythe operator grasping the handle 45, and gives him a warning slgnal tolet go.

The length of board just drawn along is now lying flat on the board fromits outer end to a point a certain distance from the opposite end whichis still attached to the remainder of the continuous stretch of formedboard and is depending from the raised apron 28.

The board is then cut across by pulling theport for the boardthereabove, and also a fixed cutting edge with which the movable cutterco-acts. I

The cutter being drawn across the board and clear of the same, may beleft where it is halted, or returned to its starting point, depending onthe desire and convenience of the operator.

The cut end of the board will now drop onto the truck 62. The truck 36is now returned toward the apron 28, with the jaws open to engage theend of the board resting on said apron. As the jaws move close to theapron 28, the latter is lowered, leaving the unsupported end of theboard in the clear, so that the lower jaw 39 may pass under the same,and the upper jaw 40 thereover.

Just before the jaws move into engagement with the board, the lever 55is engaged by the fixed arm 56, and the racks 38, and the jaws supportedby the racks, aremoved upwardly a distance equal to the thickness of theboard deposited on the truck 62. 7

About the same time the platform 16 is moved vertically by manipulationof the handwheel 27 so as to cause the projecting end of the board toabout rest on the lower jaw 39 when the latter moved under the board,since it is the upper jaw only which moves to clamp the jaws together.

The parts now being back in the same positions as stated at the outsetof the above description of operations, another and duplicate cycle ofmovement as that above outlined is about to start, and hence further-description is unnecessary.

From the foregoing description of how the board is handled for stackingit will readily appear that here too I have provided a method by whichthe tea-ring, scuffing and buckling of the wet, tender paper is avoided.

Having succeeded in both forming the board and stacking it to harden andset, all problems are solved, since, after hardening and setting, theboard made of the unretarded paper is more easily handled and produces amore uniformly commercial board than that made of the retarded paper. Byreason of the fact that the moisture quickly permeates the unretardedpaper this causes the same to quickly stretch to the limit so that whenthe board hardens and sets and is dried ready for marketing the paperadheres smoothly and permanently to the plastie core and will have notendency to curl up or peel therefrom.

From the foregoing description it will be readily seen that I haveproduced such a method as substantially fulfills the objects of theinvention as set forth herein.

Having thus described my inventionwhat I claim as new and useful anddesire to secure by Letters Patent is 1. The method of making wall boardconsisting sisting in advancing plastic material between surface sheetsto form the board, applying a uniform frictional dragging pressure tothe surface of the advancingboard continuously easing the surface sheetsagainst the dragging pressure, advancing the board to a desired lengthbeyondthe point of such dragging pressure and then severing the same.

2. The method of making wall board consisting in advancing plasticmaterial between surface sheets to form the board, advancing the formedboard a certain distance by applying a frictional draggin pressure toone surface of the advancin oard, clam ing the free end of the boarclatthe end 0 dragging pressure and advancing the board from that point insemisuspended-position' over a plane surface, then severing the boardind allowing it to drop on such plane surace.

3. The method of making wall board consisting in advancing a sheet ofpaper and adhering plastic material thereto to make a flat board,applying a uniform draggin pressure over the surface area of the boarand continuously easing the paper against the dragging pressure.

4. The method of making wall board consisting in advancing a sheet ofpaper and adhering plastic material thereto to make av flat board,applying a uniform draggin pressure over the surface area of the boarsnubbing the advance of the paper sheet to retard its movement exceptwhen the dragging pressure is applied, and slightly easing the paperagainst the dragging pressure.

5. The method of making wall board consisting in advancing plasticmaterial between surface sheets to form the board, subjectin the boardto a zone of uniformly applie dragging pressure, continuously easing thesurface sheets against the dragging pressure. advancing the board beyondsuch zone, and severing the same.

6. The method of making wall board consisting in advancing plasticmaterial between surface sheets to orm the board, subjecting the boardto a zone of uniformly applied dragging pressure, continuously easingthe surface sheets against the dragging pressure, advancing the boardbeyond such zone, severing same, and stacking the severed lengths.

7. The method of making wall board consisting in advancing plasticmaterial between surface sheets to form the board, subjectin the boardto a zone of uniformly applie dragging pressure, advancing the boardbeyond such zone in uniformly suspended relation to a desired length,and severing the same.

8. The method of making wall board consurfacesheets to form the board,advancing in advancingplastic material between I the board to a desiredlength, applying a JOHN F.

the board and severing the same in desired uniform pull to the free edgeof the board lengths andstackin the same and maintainand pulling sameover a surface in a plane 10 ing the plane of a vancement of the boardlower than the board while maintaining the constant with respect to thetop of the stack. plane of the pull at a spaced distance from 9. Themethod of making wall board conthe plane of the surface, and thensevering sisting in advancing plastic material between the board anddropping it upon the surface. surface sheets to form the board,advancing In testimony whereof I aflix m signature.

MAK OWSKI.

